Laundry treating apparatus indicating energy efficiency and method for indicating energy efficiency thereof

ABSTRACT

A laundry treating apparatus may include a drum that receives laundry item therein, a heat pump that circulates a heating medium, a compressor that compresses the heating medium, a condenser that heats air to be transmitted to the drum, an expander that expands the heating medium, and an evaporator that cools air transmitted from the drum. A heater may re-heat air heated by the heat pump, and a sensing device may sense a state, such as temperature, of the heating medium. A controller may calculate energy efficiency based on the sensed state of the heating medium. Energy related information including the calculated energy efficiency may be displayed on a display so that energy efficiency may be monitored real time.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. §119 to KoreanApplication No. 10-2012-0117468 filed on Oct. 22, 2012, whose entiredisclosure is hereby incorporated by reference.

BACKGROUND

1. Field

This relates to a laundry treating apparatus, and more particularly, toa laundry treating apparatus capable of calculating and indicatingenergy efficiency, and a method for indicating energy efficiency of sucha laundry treating apparatus.

2. Background

A laundry treating apparatus may supply hot air may to an interior of adrum to evaporate moisture from laundry that has gone through a wash andspin cycle. In, for example, a dryer, a drum may be rotatably installedwithin a body, a driving motor may drive the drum, a blower may blow airinto the drum, and a heater may heat air to be introduced into theinterior of the drum. The heater may use, for example, electricalresistance heat or combustion generated by burning gas. Air releasedfrom a drum of a laundry treating apparatus may contain moisture fromthe laundry within the drum, and have of high temperature and humidity.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to thefollowing drawings in which like reference numerals refer to likeelements wherein:

FIG. 1 is a perspective view of a laundry treating apparatus accordingto an embodiment as broadly described herein;

FIG. 2 is a perspective view of an internal structure of the laundrytreating apparatus shown in FIG. 1;

FIG. 3 illustrates a heat pump and a sensing device illustrated in FIG.2;

FIG. 4 is a block diagram of a system for indicating energy efficiencyof the laundry treating apparatus shown in FIG. 1;

FIG. 5 is a flow chart of a process of indicating energy efficiencycarried out by the system shown in FIG. 4;

FIG. 6 is a pressure-enthalpy diagram of a heating medium circulating ina heat pump;

FIG. 7 illustrates a display of the laundry treating apparatus shown inFIG. 1;

FIG. 8 is a block diagram of a system for indicating energy efficiencyof the laundry treating apparatus shown in FIG. 1, according to anotherembodiment;

FIG. 9 is a flow chart of a process of indicating energy efficiency anda saved power rate carried out by the system shown in FIG. 8; and

FIG. 10 illustrates a display according to an embodiment as broadlydescribed herein.

DETAILED DESCRIPTION

Hereinafter, embodiments will be described in detail with reference tothe accompanying drawings such that they may be easily practiced bythose skilled in the art. If a detailed explanation for a related knownfunction or construction is considered to unnecessarily divert thedisclosure, such explanation will be omitted and considering to beunderstood by those skilled in the art.

Dryers may be classified into a condensing-type dryer (or circulatingdryer) and an exhaust-type dryer according to the way in which hightemperature, high humidity is treated. In the case of thecondensing-type dryer, air having high temperature and humidity may becirculated, rather than being discharged to the outside, and cooled asit is circulated to have a temperature lower than a dew-pointtemperature, thus condensing moisture in the air. In the case of theexhaust-type dryer, air high temperature, high humidity air which haspassed through the drum may be directly discharged to the outside.

In the case of the condensing-type dryer, in order to condense airdischarged from the drum, air may be cooled to below a dew point, andbefore it is supplied again to the drum, air may be heated by theheater. In this case, as air is cooled during the condensing process,thermal energy loss may occur, and an additional heater may be used inorder to heat air to a temperature sufficient for drying.

In the case of the exhaust-type dryer, high temperature, high humidityair may be discharged to the outside, room temperature ambient air maybe introduced, and the ambient air may be heated to reach a requiredtemperature level by a heater. In particular, high temperature airdischarged to the outside may contain thermal energy transmitted by theheater, but since it is discharged to the outside, heat efficiency maybe degraded.

A laundry treating apparatus capable of enhancing energy efficiency byrecovering energy used to generate hot air and energy discharged to theoutside may include a heat pump having, for example, two heatexchangers, a compressor, and an expander, to recover energy fromexhaust hot air and reuse it to heat air supplied to a drum.

Such a heat pump may transmit thermal energy of high temperature, highhumidity air introduced from the drum through the evaporator to arefrigerant, and transmit thermal energy of the refrigerant to airflowing into the drum through the condenser, thereby generating hot airusing discarded energy. The use of such a heat pump may enhance energyefficiency in comparison drying using a heater.

However, a laundry treating apparatus having only a heat pump may have arelatively long drying time compared to that of a laundry treatingapparatus having a heater. Thus, a laundry treating apparatus mayinclude both a heater for heating again air heated while passing througha condenser, in addition to a heat pump.

However, because a laundry treating apparatus including a heat pump doesnot necessarily specify energy efficiency when a drying process isactually performed, energy efficiency. Also, since substantial energyefficiency cannot be known, a substantially reduced amount of energycannot also be known and corresponding reduction in energy consumptionmay be difficult to assess.

The embodiment illustrated in FIGS. 1 through 3 is applied to a dryer,but embodiments are not limited only to a dryer and may also beapplicable to a certain laundry treating apparatus for drying laundry bysupplying hot air into a drum, e.g., a washing machine having a dryingfunction, and the like.

Hereinafter, a laundry treating apparatus indicating energy efficiency,according to an embodiment, will be described in detail with referenceto FIGS. 1 through 3. The laundry treating apparatus may include a body100 forming the exterior and a drum 110 rotatably installed within thebody 100. The drum may be rotatably supported by, for example, asupporter, provided at at least one of a front or rear end thereof.

The body 100 may include a door 101 for opening and closing one end ofthe drum 110 to allow a drying target (or a drying object) to be putinto the drum 110. A display 102 displaying information such as a dryingprocess mode, a drying progress degree, real-time energy efficiency, andthe like, when a drying process is performed, may be provided on thebody 100.

An intake duct 120 forming part of a flow path for transmitting air tothe interior of the drum 110 may be installed at a lower surface of thedrum 110. An end portion of the intake duct 120 may be connected to anend portion of a back duct 122 that extends in a vertical direction ofthe body 100, between the intake duct 120 and the drum 110, to supplyair from the intake duct 120 to the interior of the drum 110. Thus, aflow path transmitting air to the drum 110 may be formed by the intakeduct 120 and the back duct 122.

Air supplied through the flow path may be introduced into the body 100from the outside through an intake port formed in a rear surface or alower surface of the body 100 and transferred to the intake duct 120. Anintake fan 185 may be installed in an end portion of the intake duct 120to induce air flow. Namely, according to rotation of the intake fan 185,air from within the body 100 may be introduced into the intake duct 120,and pressure within the body 100 may be lowered accordingly to allowambient air to be introduced into the body 100 through the intake port.

In certain embodiments, it is not necessary for air within the body 100to be introduced into the flow path, and an example in which only airfrom outside of the body 100 is introduced may also be considered.

A condenser 130 may be installed in front of the fan 185 (i.e., at anupper stream side on the basis of an air flow path). The condenser 130,together with an evaporator 135, a compressor 150, and an expander 160,may together form a heat pump having a heating medium circulatingtherethrough. The heating medium may be compressed by the compressor 150and subsequently supplied to the condenser 130 through a firstconnection pipe 191 connecting the compressor 150 and the condenser 130.The heating medium may emit heat in the condenser 130 and subsequentlybe supplied to the expander 160 through a second connection pipe 192connecting the condenser 130 and the expander 160. The heating mediumexpanded by the expander 160 may be supplied to the evaporator 135through a third connection pipe 193 connecting the expander 160 and theevaporator 135. The heating medium may absorb heat in the evaporator 135and be subsequently supplied to the compressor 150 through a fourthconnection pipe 194 connecting the evaporator 135 and the compressor150. In this manner, the heating medium may circulate in the heat pump.In the present disclosure, the heating medium acts as a refrigerant inthe evaporator 135, so the heating medium will be referred to as arefrigerant.

In the condenser 130, a single refrigerant pipe 134 forming a condenserheating medium pipe is disposed an air flow path, and a plurality ofheat dissipation fins 132 are installed to be perpendicular with respectto the refrigerant pipe 134. Namely, the refrigerant pipe 134 maypenetrate through the heat dissipation fins 132 disposed in piles (or inlayers) at predetermined intervals therebetween. One end of therefrigerant pipe 134 may be connected to the first connection pipe 191to receive a compressed refrigerant from the compressor 150, and theother end of the refrigerant pipe 134 may be connected to the secondconnection pipe 192 to supply a refrigerant to the expander 160.Meanwhile, since the intake fan 185 is positioned downstream of thecondenser 130, air drawn in by the intake fan 185 may be heat-exchangedwith the refrigerant while passing through the heat dissipation fins 132of the condenser 130, and thus, air having an increased temperature maybe introduced into the interior of the drum 110. A linear expansionvalve whose opening degree is controlled by an electrical signal may beused as the expander 160.

A heater 170 may be installed within the back duct 122 to further heatair in a case in which air is not sufficiently or quickly heated by onlythe condenser 130. The heater 170 may also be installed in the intakeduct 120. Air heated while passing through the condenser 130 and theheater 170 may be introduced into the interior of the drum 110 andsubsequently dry a drying target accommodated within the drum 110.

Thereafter, the hot air, having absorbed moisture from the dryingtarget, may be transmitted to an exhaust duct 140 by an exhaust fan 180,heat-exchanged with a refrigerant having a low temperature passingthrough the interior of the evaporator 135 disposed in an end portion ofthe exhaust duct 140, and subsequently discharged to the outside of thebody 100. Through the heat-exchanging process, the air, in a state inwhich it has a lower temperature and humidity, may be discharged to theoutside. At this time, a portion of thermal energy of the air dischargedfrom the drum 110, passing through the evaporator 135, may betransmitted to the refrigerant, and the thermal energy may be used againto heat air in the condenser 130. Thus, since thermal energy, whichwould otherwise be discarded, is collected and recycled to generate hotair, energy consumption may be reduced. Also, in a case in which quickdrying is required, the heater 170, providing additional heating, may beoperated, whereby drying may be performed flexibly.

A sensing device may sense a quantity/state of a refrigerant. In detail,the sensing device may include a plurality of temperature sensors 175,176, 177, 178, and 179. The first temperature sensor 175 may measure atemperature of a refrigerant introduced into the evaporator 135. Thefirst temperature sensor 175 may be attached to a portion of the thirdconnection pipe 193 adjacent to the evaporator 135. A temperature of therefrigerant introduced into the evaporator 135 may be inferred bymeasuring a surface temperature of the evaporator 135 of the thirdconnection pipe 193. Thus, a temperature of the refrigerant may besensed by simply attaching the first temperature sensor 175 to a surfaceof the third connection pipe 193.

As described above, the second temperature sensor 176 may be attached aportion of the fourth connection pipe 194 adjacent to the evaporator 135to sense a temperature of a refrigerant discharged from the evaporator135. The third temperature sensor 177 may be attached to a portion ofthe first connection pipe 191 adjacent to the condenser 130 to sense atemperature of a refrigerant introduced into the condenser 130. Thefourth temperature sensor 178 may be attached to a portion of the secondconnection pipe 192 adjacent to the condenser 130 to sense a temperatureof a refrigerant discharged from the condenser 130. The fifthtemperature sensor 179 may be attached to a portion of the firstconnection pipe 191 adjacent to the compressor 150 to sense atemperature of a refrigerant discharged from the compressor 150.

FIG. 4 is a block diagram of a system for indicating energy efficiencyof the laundry treating apparatus shown in FIG. 1, FIG. 5 is a flowchart of a process of indicating energy efficiency, and FIG. 6 is apressure-enthalpy diagram of a heating medium circulating in a heatpump. A controller for the laundry treating apparatus according to anembodiment will be described in detail with reference to FIGS. 1 through6.

The controller 200 may calculate energy efficiency in real time, basedon a quantity of a heating medium of the heat pump. In detail, asillustrated in FIG. 4, the controller 200 may be electrically connectedto the plurality of temperature sensors 175, 176, 177, 178 and 179, andmay calculate an amount of energy (Qe) absorbed by refrigerant in theevaporator 135 and an amount of energy supplied by refrigerant in thecondenser 130 based on a temperature of the heating medium, and maycalculate energy efficiency therefrom. The controller 200 may beelectrically connected to the display 102, and may transmit this energyefficiency information to the display 102.

A method for calculating and displaying energy efficiency will bedescribed in detail with reference to FIG. 5.

First, a refrigerant temperature sensing operation (S110) is performedby the plurality of temperature sensors 175, 176, 177, 178 and 179. Arefrigerant temperature sensed by the first temperature sensor 175 isinput as T1 to the controller 200. A refrigerant temperature sensed bythe second temperature sensor 176 is input as T2 to the controller 200.A refrigerant temperature sensed by the third temperature sensor 177 isinput as T3 to the controller 200. A refrigerant temperature sensed bythe fourth temperature sensor 178 is input as T4 to the controller 200.A refrigerant temperature sensed by the fifth temperature sensor 179 isinput as T5 to the controller 200.

Next, in an energy efficiency calculation operation, energy efficiencyis calculated by the controller 200 based on the refrigerant temperaturesensed in the sensing operation (S110). In detail, the energy efficiencycalculation operation may include a first calculation operation (S120),a second calculation operation (S130), and a third calculation operation(S140).

In the first calculation operation (S120), an enthalpy variation of therefrigerant and a flow rate of the refrigerant may be calculated by thecontroller 200.

In detail, the controller 200 may calculate a variation (Δhe) between anenthalpy of the refrigerant introduced into the evaporator 135 and anenthalpy of the refrigerant discharged from the evaporator 135 based onthe temperatures T1 and T2, and may calculate a variation (Δhc) betweenan enthalpy of the refrigerant introduced into the condenser 130 and anenthalpy of the refrigerant discharged from the condenser 130 based onthe temperatures T3 and T4. The enthalpy variation (Δhe) in theevaporator 135 and the enthalpy variation (Δhc) in the condenser 130 maybe calculated by calculating an enthalpy according to a quantity ofstate of the refrigerant in the graph of FIG. 6 corresponding to therespective temperatures T1, T2, T3 and T4. For example, in a case inwhich when the temperature T1 of the refrigerant corresponds to a pointA and the temperature T2 of the refrigerant corresponds to a point B,the enthalpy variation (Δhe) of the refrigerant has a magnitude from Ato B along an x axis. In a case in which when the temperature T3 of therefrigerant corresponds to a point C and the temperature T4 of therefrigerant corresponds to a point D, the enthalpy variation (Δhc) ofthe refrigerant has a magnitude from C to D along the x axis. In thegraph of FIG. 6, the x axis represents enthalpy (KJ/Kg) and the y axisrepresents pressure (Bar).

A flow rate (m) of the refrigerant may be obtained by multiplying aspecific volume (V) of the heating medium determined according to thetemperature T5 by a revolution per minute of the compressor 150 (R), andby capacity (c) of the compressor 150 as expressed by Equation 1 below.

m=R*C*V  [Equation 1]

In the second calculation operation (S130), the controller 200 maycalculate an amount of energy (Qe) absorbed by the refrigerant in theevaporator 135 by multiplying the enthalpy variation (Δhe) of therefrigerant in the evaporator 135 and the flow rate (m) of therefrigerant as expressed by Equation 2 below. The controller may alsocalculate an amount of energy supplied by the refrigerant in thecondenser 130 by multiplying the enthalpy variation (Δhc) of therefrigerant in the condenser 130 and the flow rate (m) of therefrigerant as expressed by Equation 3 below.

Qe=m*Δhe  [Equation 2]

Qc=m*Δhc  [Equation 3]

Thereafter, in the third calculation operation (S140), the controller200 may calculate energy efficiency (Eff) of the heat pump as expressedby Equation 4 below.

$\begin{matrix}{{Eff} = \frac{Qc}{{Qc} - {Qe}}} & \left\lbrack {{Equation}\mspace{14mu} 4} \right\rbrack\end{matrix}$

Thereafter, in an output operation (S150), the controller 200 maytransmit the calculated energy efficiency Eff information to the display102, and the display 102 may indicate the energy efficiency by %.

Thereafter, in a drying determination operation (S160), the controller200 may determine whether a drying process of the dryer is beingperformed. When it is determined that a drying target, or laundry item,is being continuously dried, the controller 200 may return to thetemperature sensing operation (S110) and perform the first, second andthird calculation operations (S120, S130 and S140) to re-calculateenergy efficiency (Eff). Then, during the output operation (S150), thecontroller 200 may transmit the re-calculated energy efficiency (Eff) tothe display 102, and the display 102 may display the re-calculatedenergy efficiency (Eff) in real time. When the controller 200 determinesthat the drying process has been completed in the drying determinationoperation (S160), energy efficiency (Eff) is no longer re-calculated andthe calculation is terminated.

FIG. 7 is a plan view illustrating a display 102 of the exemplaryapparatus illustrated in FIG. 1. The display 102 and a method fordisplaying information regarding energy by the display 102 will bedescribed in detail with reference to FIG. 7. As illustrated, thedisplay 102 may display information regarding a drying process andinformation regarding energy.

In detail, a progress degree of a drying process may be output aspercentage (%) in a upper left portion of the display 102, and in FIG.7, 58% is displayed. A process degree of a drying process may also beindicated by a degree to which an empty horizontal bar is filled (or aprogress bar) to provide quick visual recognition. In FIG. 7, ahorizontal bar is disposed below the indication of 58%. Also, ananticipated remaining duration of the drying process may be displayed(or indicated) by, for example, minute and second in an upper rightportion of the display 102. “DRY” indicating that a drying process maybe underway is output in a central left portion of the display 102, andenergy efficiency (Eff) transmitted from the controller 200 may beoutput as percentage (%) in a central right portion of the display 102.“ECO OFF” and “ECO ON” may be selectively output in a lower left portionof the display 102 according to whether the heater 170 is operatedduring a drying process. For example, when only the heat pump isactuated during the drying process, “ECO ON” may be output, and when theheat pump and the heater 170 are actuated together during the dryingprocess, “ECO OFF” may be output.

Information displayed on the display 102 is not limited to thisarrangement, and various types of information regarding the dryingprocess and information regarding energy may be displayed in this oranother manner as appropriate. Positions in which various types ofinformation are displayed on the display 102 may be changed withoutbeing limited to the foregoing positions.

FIG. 8 is a block diagram system for indicating energy efficiencyaccording to another embodiment as broadly described herein, FIG. 9 is aflow chart of a process of indicating energy efficiency and a savedpower rate by the system shown in FIG. 8, and FIG. 10 is a view of adisplay shown in FIG. 9, according to an embodiment.

A laundry treating apparatus capable indicating energy efficiencyaccording to an embodiment as broadly described herein may include dryerhaving a heat pump and the heater 170, and the heat pump may include thecondenser 130, the compressor 150, the evaporator 135, and the expander160, as previously described. The laundry treating apparatus accordingto another embodiment may also include a controller 200′, a display 102′and a communication device 300.

The communication device 300 may be connected to an external device 400in a wired/wireless communication manner to receive power informationincluding, for example, information regarding power rate time slots andinformation regarding time. The communication device 300 may beconnected to the external device 400 in an appropriate manner totransmit and receive data, such as, for example, power linecommunication, wireless LAN, the Internet, Zigbee, serial communication,and the like.

The external device 400 may be one or more of a power-related devicesuch as, for example, a home server, a smart meter, and the like, and anexternal power system, in which power information may be stored.

The power rate time slot information received from the external device400 may include, for example, information regarding a general time slotand a peak time slot. The peak time slot is a time slot in which anoverall amount of electricity consumption is at an elevated level sopower available to be supplied to each household, or the like, isreduced to below a predetermined value. The peak time slot may be set bya power provider based on data such as statistics, and the like, orresults observed in real time. The general time slot may be a time slotother than the peak time slot. In general, the power provider may chargea relatively high rate for power consumed during the peak time slot, soupon receiving information regarding a power rate time slot, a powerrate, for example, a cost to operate during a particular time period maybe precisely calculated.

The controller 200′ may calculate energy efficiency and a saved powerrate in real time based on a quantity of state of the heating medium ofthe heat pump. Referring to FIG. 8, the controller 200′ may beelectrically connected to the plurality of temperature sensors 175, 176,177, 178 and 179. The configuration and function of the temperaturesensors 175, 176, 177, 178 and 179 have been described above withreference to FIGS. 2 and 3.

The controller 200′ calculate an amount of energy Qe absorbed by arefrigerant in the evaporator 135 based on the temperature of a heatingmedium sensed by the sensor and an amount of energy Qc supplied by therefrigerant in the condenser 130, and may calculate energy efficiencytherefrom. The controller 200′ may also be electrically connected to thecommunication device 300 to receive power information as describedabove, and may calculate saved power rates based on the powerinformation and the energy Qe absorbed by the refrigerant in theevaporator 135.

The controller 200′ may also be electrically connected to the display102′ to transmit information regarding energy to the display 102′. Theinformation regarding energy may include energy efficiency, the energyQe absorbed by the heating medium in the evaporator 135, the energy Qcsupplied by the heating medium in the condenser 130, and the saved powerrate.

A method for calculating energy efficiency and a saved power rate andindicating the calculated energy efficiency on the display will bedescribed in detail with reference to FIGS. 5 and 10.

First, a temperature sensing operation (S210), like the temperaturesensing operation (S110) as described above with reference to FIG. 5, isperformed, and the temperatures T1, T2, T3, T4 and T5 of the refrigerantare sensed by the sensors.

Next, an energy efficiency calculating operation is performed in whichenergy efficiency of the heat pump is calculated by the controller 200′based on the temperature sensed in the temperature sensing operation(S210). The energy efficiency calculating operation may include a firstcalculation operation (S220), a second calculation operation (S230), anda third calculation operation (S310).

In the first calculation operation (S220), like the first calculationoperation (S120) described above with reference to FIGS. 5 and 6, anenthalpy variation (Δhe) of the refrigerant in the evaporator 135 and anenthalpy variation (Δhc) of the refrigerant in the condenser 130 may becalculated by the controller 200′, and a flow rate (m) of therefrigerant may be calculated by the controller 200′. In the secondcalculation operation (S230), like the second calculation operation(S130) described above with reference to FIG. 5, an amount of energy(Qe) absorbed by the refrigerant in the evaporator and an amount ofenergy (Qc) supplied by the refrigerant in the condenser may becalculated by the controller 200′. In the third calculation operation(S310), like the third calculation operation (S140) described above withreference to FIG. 5, energy efficiency Eff of the heat pump may becalculated by the controller 200′.

A saved power rate calculation step (S410) may be performedsimultaneously with the third calculation operation (S310). In the savedpower rate calculation operation (S410), a saved power rate EC may becalculated by the controller 200′ based on the power informationreceived from the communication device 300 and the amount of energy (Qe)absorbed by the refrigerant in the evaporator 135. In detail, when powerinformation is power rate (E) per kWh unit, saved power rate (EC) may becalculated as a value obtained by all of the power rate (E) per kWhunit, an amount of energy (Qe) absorbed by the refrigerant in theevaporator 135, and an initial drying operation time (t minutes/60).Here, the drying operation time t may be measured in minutes. The savedpower rate EC calculated in this manner may be accumulated to becalculated in real time while the drying process is performed asdescribed hereinafter.

EC=EC+E*Qe*(t/60)  [Equation 5]

Thereafter, in an output operation (S500), energy efficiency Effcalculated by the controller 200′ may be displayed by percentage by thedisplay 102′. Also, in the output operation (S500), informationregarding energy, e.g., the saved power rate (EC), may be displayed, forexample, in monetary units, on the display unit 102′.

In the output operation (S500) as described above, when the energyefficiency and saved power rate are output to the display 102′, thecontroller 200′ may determine whether the drying process of the dryer isbeing performed in a drying determination operation (S600).

When it is determined that a drying target, or laundry item, is beingcontinuously dried, the controller 200′ may return to the temperaturesensing operation (S210) and perform the first, second and thirdcalculation operations S220, S230 and S310 to re-calculate energyefficiency Eff. In the output operation (S500), the energy efficiencyEff may be displayed in real time on the display 102′ in the outputoperation (S500).

Also, when it is determined that the drying target is being continuouslydried, the controller 200′ may return to the temperature sensingoperation (S210) after t minutes and performs the first calculationoperation (S220) and the second calculation operation (S230) tore-calculate energy Qe absorbed by the refrigerant in the evaporator. Inthe saved power rate calculation operation (S410), the controller 200′may calculate the accumulated saved power rate EC by adding the powerrate saved for t minutes to the previously calculated power rate EC. Inthe output operation (S500), the saved power rate EC may be displayed,for example, in monetary units, on the display 102′.

The foregoing operations may be repeatedly performed during a dryingoperation and the controller 200′ may calculate information regardingenergy including energy efficiency of the heat pump, the amounts (Qe andQc) of energy absorbed or supplied by the refrigerant, and the savedpower rate in real time, and may transmit this information to thedisplay 102′. The display 102′ may display the information regardingenergy in real time.

According to the foregoing configuration, since energy efficiency, asubstantially saved power rate, and the like, may be calculated anddisplayed in real time, a user may directly check high energy efficiencyof the laundry treating apparatus and corresponding economical effects.

Thereafter, in the drying determination operation (S600), when it isdetermined that the drying process is complete, the energy efficiencyEff and the saved power rate EC are no longer re-calculated.

An initial screen of the display 102′ may be substantially the same as ascreen of the display 102 as described above with reference to FIG. 7.In certain embodiments, each display may be configured as a touch screenand may sense a contact applied thereto in a resistive manner or acapacitive manner.

When a touch applied to a portion of the display is sensed, the screenillustrated in FIG. 7 may be changed to the screen illustrated in FIG.10. Namely, when a touch applied to the portion in which energyefficiency is displayed is sensed, the display may further displaydetailed information regarding energy efficiency. For example, asdescribed above, the amount of energy Qe absorbed by the refrigerant inthe evaporator 135 and the amount of energy Qc supplied by therefrigerant in the condenser 130 may be displayed together in real timetogether with energy efficiency. Also, the saved power rate EC may bedisplayed in real time on the display. Here, the saved power rate EC maybe accumulated and re-calculated at every t minutes, so a numericalvalue thereof may be changed and displayed at every t minutes. Thecalculated energy efficiency may be displayed by percentage (%), forexample, at a right portion of the display. A configuration of the heatpump may be simply displayed, for example, at a left portion of thedisplay, indicating that the heat pump is in operation. Besides, “Dry”and whether the heater 170 is operated may be further displayed asdescribed above with reference to FIG. 7.

However, a display as embodied and broadly described herein is notlimited thereto and a current screen thereof may be changed to a screendisplaying information regarding energy efficiency in detail by, forexample, a button. Namely, it may be configured such that the user maymanipulate a button provided separately from the display to change thescreen. Also, the method in which information regarding energy isdisplayed on the screen of the display and the content of theinformation regarding energy are not limited to the foregoing content.

As the present features may be embodied in several forms withoutdeparting from the characteristics thereof, it should also be understoodthat the above-described embodiments are not limited by any of thedetails of the foregoing description, unless otherwise specified, butrather should be considered broadly within its scope as defined in theappended claims, and therefore all changes and modifications that fallwithin the metes and bounds of the claims, or equivalents of such metesand bounds are therefore intended to be embraced by the appended claims.

A laundry treating apparatus having a heat pump capable of indicatingenergy efficiency of the heat pump in real time when a drying process isperformed, and a method for indicating energy efficiency of such alaundry treating apparatus, are provided.

A laundry treating apparatus having a heat pump capable of indicating apower rate reduced according to an amount of energy re-used when adrying process is performed, and a method for indicating energyefficiency of such a laundry treating apparatus, are provided.

A laundry treating apparatus having a heat pump capable of usefullydisplaying information regarding energy efficiency of the heat pumpthrough a display unit thereof when a drying process is performed, and amethod for indicating energy efficiency of such a laundry treatingapparatus, are provided.

A laundry treating apparatus, as embodied and broadly described herein,may include a drum configured to accommodate a drying target, a heatpump configured to cool air transmitted from the drum and subsequentlyheat the same, a heating unit configured to re-heat air heated by theheat pump; a sensing unit configured to sense a quantity of state of theheating medium, a control unit configured to calculate energy efficiencyon the basis of the quantity of state of the heating medium; and adisplay unit configured to display information regarding energyincluding the energy efficiency.

The heat pump may include a heating medium that circulates; a compressorconfigured to compress the heating medium, a condenser configured toheat air transmitted to the drum, an expander configured to expand theheating medium, and an evaporator configured to cool air transmittedfrom the drum.

The control unit may calculate the energy efficiency by calculating anamount of energy absorbed by the heating medium in the evaporator and anamount of energy supplied by the heating medium in the condenser.

The quantity of the heating medium may include a temperature of theheating medium.

The sensing unit may include a plurality of temperature sensing units.

The plurality of sensing units may be installed in a heating mediuminlet of the evaporator, a heating medium outlet of the evaporator, aheating medium inlet of the condenser, and a heating medium outlet ofthe condenser, respectively.

The control unit may calculate energy absorbed by the heating medium inthe evaporator on the basis of the heating medium inflow temperature andoutflow temperature of the evaporator, and calculate energy supplied bythe heating medium in the condenser on the basis of the heating mediuminflow temperature and outflow temperature of the condenser.

The information regarding energy may include an amount of energyabsorbed by the heating medium in the evaporator and an amount of energysupplied by the heating medium in the condenser.

The clothes treating apparatus may further include a communication unitconnected to an external device in a wired/wireless communicationmanner, and configured to receive power information includinginformation regarding a power rate time slot and time information.

The control unit may further calculate a power rate saved by the heatpump on the basis of the power information and the quantity of state ofthe heating medium, and the information regarding energy may include thesaved power rate.

The control unit may calculate the saved power rate on the basis ofenergy absorbed by the heating medium in the evaporator.

The sensing unit may include a plurality of temperature sensing units.The plurality of temperature sensing units may be installed in theheating medium inlet and outlet of the evaporator, respectively.

The control unit may calculate an amount of energy absorbed by theheating medium in the evaporator on the basis of the heating mediuminflow temperature of the evaporator and the heating medium outflowtemperature of the evaporator.

The display unit may further display detailed information regardingenergy efficiency including an amount of energy absorbed by the heatingmedium in the evaporator by external pressure through a touch screen ora button and an amount of energy supplied by the heating medium in thecondenser.

A method for indicating energy efficiency of a laundry treatingapparatus, as embodied and broadly described herein, may include asensing operation of sensing a quantity of state of a heating mediumthat circulates in a heat pump; an energy efficiency calculatingoperation of calculating energy efficiency of the heat pump on the basisof the quantity of state of the heating medium, and an output operationof displaying information regarding energy including the energyefficiency.

The energy efficiency calculating operation may include calculating anamount of energy absorbed by the heating medium in the evaporator of theheat pump and calculating an amount of energy supplied by the heatingmedium in the condenser of the heat pump.

In the sensing operation, a temperature of the heating medium introducedto the evaporator, a temperature of the heating medium discharged fromthe evaporator, a temperature of the heating medium introduced to thecondenser, and a temperature of the heating medium discharged from thecondenser may be sensed, respectively.

The method may further include a power rate calculating operation ofcalculating a saved power rate on the basis of an amount of energyabsorbed by the heating medium in the evaporator. Here, the informationregarding energy may further include the saved power rate.

In the sensing operation, a temperature of the heating medium introducedto the evaporator and a temperature of the heating medium dischargedfrom the evaporator may be sensed.

In the power rate calculating operation, power rates saved for apredetermined period of time may be accumulated and re-calculated atevery predetermined time.

When a drying process is performed in a laundry treating apparatushaving a heat pump, as embodied and broadly described herein energyefficiency may be checked real time, energy efficiency may be simplycalculated by sensing a temperature of a heating medium circulating inthe heat pump, energy absorbed by a heating medium and energy suppliedby the heating medium may be checked real time, a power rate reduced byenergy re-used by the heat pump may be checked in real time and, whenenergy efficiency of the heat pump is equal to or lower than aparticular numerical value, the drying process mode may be appropriatelychanged to enhance energy efficiency and save power.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A laundry treating apparatus, comprising: a drumconfigured to receive laundry items therein; a heat pump configured tocirculate a heating medium, the heat pump including a compressorconfigured to compress the heating medium, a condenser configured toheat air to be transmitted to the drum, an expander configured to expandthe heating medium, and an evaporator configured to cool air transmittedfrom the drum; a heater configured to re-heat air heated by the heatpump; a sensing device configured to sense at least one state value ofthe heating medium; a controller configured to calculate energyefficiency based on the at least one state value of the heating medium;and a display configured to display energy related information and thecalculated energy efficiency.
 2. The apparatus of claim 1, wherein thecontroller is configured to calculate the energy efficiency bycalculating an amount of energy absorbed by the heating medium in theevaporator and an amount of energy supplied by the heating medium in thecondenser.
 3. The apparatus of claim 2, wherein the at least one statevalue of the heating medium includes a temperature of the heating mediumat least one point in a circulation path of the heating medium throughthe heat pump.
 4. The apparatus of claim 3, wherein the sensing devicecomprises a plurality of temperature sensors respectively installed in aheating medium inlet of the evaporator, a heating medium outlet of theevaporator, a heating medium inlet of the condenser, and a heatingmedium outlet of the condenser.
 5. The apparatus of claim 2, wherein theenergy related information comprises an amount of energy absorbed by theheating medium in the evaporator and an amount of energy supplied by theheating medium in the condenser.
 6. The apparatus of claim 5, whereinthe display is configured to display an amount of energy absorbed by theheating medium in the evaporator and an amount of energy supplied by theheating medium in the condenser in response to an external inputreceived at a touch screen or a button operably coupled to the display.7. The apparatus of claim 1, wherein the controller is configured tocalculate a power rate saved by the heat pump based on the at least onestate value of the heating medium, and wherein the energy relatedinformation includes the calculated saved power rate.
 8. The apparatusof claim 7, further comprising: a communication device configured tocommunicate with an external device, and to receive power informationincluding power rate time slot information, wherein the controllercalculates the saved power rate based on the power information receivedfrom the external device.
 9. The apparatus of claim 8, wherein thecontroller calculates the saved power rate based on an amount of energyabsorbed by the heating medium in the evaporator.
 10. The apparatus ofclaim 8, wherein the sensing device comprises a plurality of temperaturesensors respectively installed in a heating medium inlet and a heatingmedium outlet of the evaporator.
 11. The apparatus of claim 8, whereinthe controller accumulates power rates saved within a predeterminedperiod of time and re-calculates the accumulated saved power rate eachtime the predetermined period of time elapses.
 12. A method of operatinga laundry treating apparatus, the method comprising: performing asensing operation, comprising sensing at least one state value of aheating medium circulating in a heat pump; performing an energyefficiency calculating operation, comprising calculating energyefficiency of the heat pump; and performing an output operation,comprising displaying energy related information including thecalculated energy efficiency of the heat pump, wherein the energyefficiency calculating operation comprises: calculating an amount ofthermal energy absorbed by the heating medium in an evaporator of theheat pump based on the at least one value state of the heating medium;and calculating an amount of thermal energy supplied by the heatingmedium in a condenser of the heat pump based on the at least one statevalue of the heating medium.
 13. The method of claim 12, wherein sensingat least one state value of a heating medium comprises sensing atemperature of the heating medium introduced into the evaporator, atemperature of the heating medium discharged from the evaporator, atemperature of the heating medium introduced into the condenser, and atemperature of the heating medium discharged from the condenser.
 14. Themethod of claim 12, further comprising: performing a power ratecalculating operation, comprising calculating a saved power rate basedon an amount of energy absorbed by the heating medium in the evaporator,wherein the energy information includes the saved power rate.
 15. Themethod of claim 14, wherein sensing at least one state value of aheating medium comprises sensing a temperature of the heating mediumintroduced into the evaporator and a temperature of the heating mediumdischarged from the evaporator, and wherein performing a power ratecalculating operation comprises: determining a total amount of powerconsumed within a predetermined period of time and calculating a savedpower rate based on the total amount of power consumed and an applicablepower rate for the predetermined period of time; re-calculating thesaved power rate at predetermined intervals corresponding to thepredetermined period of time.
 16. A method of operating a laundrytreating apparatus, the method comprising: sensing a temperature of aheating medium at least one point in a circulation path of the heatingmedium through a heat pump; calculating energy efficiency of the heatpump based on the sensed temperature; and displaying energy relatedinformation related to the operation of the laundry treating apparatus,comprising: receiving power rate information from an external source;calculating an amount of power rate that has been saved within apredetermined period of time based on an amount of energy absorbed bythe heating medium circulating through the heat pump within thepredetermined period of time and the received power rate information;displaying the calculated energy efficiency and saved power rate on adisplay; re-calculating the saved power rate and the energy efficiencyat predetermined intervals corresponding to the predetermined period oftime; and re-displaying the calculated energy efficiency andre-calculated saved power rate on the display.
 17. The method of claim16, wherein calculating energy efficiency comprises: calculating anamount of thermal energy absorbed by the heating medium in an evaporatorof the heat pump based on a first temperature of the heating mediummeasured at an inlet into the evaporator and a second temperature of theheating medium measured at an outlet of the evaporator; and calculatingan amount of thermal energy supplied by the heating medium in acondenser of the heat pump based on a third temperature of the heatingmedium measured at an inlet into the condenser and a fourth temperatureof the heating medium measured at an outlet of the condenser.